Machine gun mount for aircraft



'March 21, 1933. C. G. TRIMBACH 1,902,

MACHINE GUN MOUNT FOR AIRCRAFT Filed March 21; 1930 2 Sheets-Sheet 1 a2 FIGZ.

M INYENTOR CLEM G. TR/MBACH 7 ATTORNEY I March 21, 1933- c. a. TRIMBACH 1,902

MACHINE GUN MOUNT FOR AIRCRAFT Filed March 27, 1950 2 Sheets-Sheet 2 CLEM GITR/MBAC/I ATTORNEY Patented Mar. 21, 1933 PATENT OFFICE UNITED STATES CLEM G. TUE, 01' HEHPSTEAD, NEW YORK, ASBIGNOB '10 CURTISS AEBOPIIANE &

' MOTOR COMPANY, INC, A CORPORATION OF NEW YORK imcnnm GUN ileum son Amcm'r Application filed Iarch 87, 1980. Serial Ho. 489,298.

This invention relates to. military. aeronautics and more particularly to mounts for machine guns to be used on aircraft.

Prior to my invention the usual form of a mount for a machine gun for an airplane was that known as the ring mount. This form of mount is subject to several well known disadvantages. It is very diiiicult for the gunner to climb out of a cockpit equipped with the ring mount. It is almost impossible to rotate the gun except when it has been de pressed for substantially horizontal firing. It is necessary for the gunner, while operating it, to stand in the cockpit to a large extent exposed to the fire of'enemy airplanes. It is difficult to move the gun mount about its vertical axis at any time and it is extremely diflicult to rotate it against the air blast from the propeller while the airplane is in flight.

One of the objects of my invention is to provide an improved mount for a machine gun capable of supporting the gun against the attraction of gravity and of maintaining it when desired substantially fixed a ainst the air forces-and the vibration caused y the firing of the gun itself.

A further object of my invention is to provide a mount for a machine gun so arranged that the machine gun will be capable of efficient fire throughout a relatively large range.

A further object of my invention is to increase the flexibility of machine gun operations, while the gun remains secured to its mount in the cockpit of an airplane. To accomplish this ob'ectI so arrange the parts that the force 0 gravity tends to counterbalance the force of the wind stream upon the gun. .Furthermore, I so arrange the parts that when the gunner is engaged in overhead firing, the un mount is automatically raised and when t e gunner is engaged in downward firing over the sides of the airplane, the gun mountis automatically depressed.

A further object of my invention is to minimize the space taken from the cockpit of the airplane by the machine gun mount in order that greater space may be available for photographic, radio and other apparatus. It is also an object of the invention to rearrange the parts so that'said space available for radio, photographic and other apparatus "shall be located conveniently for their operation by the observer. As shown the gun mount does not substantially restrict the shape and size of the cockpit nor does it reuire special design of the usual cockpit and uselage structure. By a special retractible feature, provision is made so that when not in use the gun may be moved rearward and downward into a pocket in the cowling aft of the g'unners cockpit thus clearing the cockpit of obstructions and reducing head resistance. 7

Further objects of the invention include the reduction of weight of the machine gun mount; the simplification of installation and removal; and the reduction of the size of the cockpit opening. 4

Further objects will be apparent from a reading of the subjoined specification and claims and from a consideration of the drawm s. n order to explain the invention more clearly, one embodiment thereof is shown in i the accompanying drawings, in which:

Fig. 1' is a side elevation of a part of an airplane equipped with a gun mount constructed according to my invention;

Fig. 2 is a plan view of the part of the airplane shown in Fig. 1 with the machine gun removed from its mounting;

Fig. 3 is a front elevation of the part of the airplane and the apparatus shown in Fig. 1;

Fig. 4 is a view of a part of the apparatus as shown in Fig. 1, on an enlarged scale to show details of the roller bearings and locking device;

Fig. 5 is a view similar to Fig. 4 taken at right angles thereto to show more particularly theadapter mount and the roller bearings;

Fig. 6 is a horizontal sectional view taken substantially on the line 6-6 of Fig. 4;

Fig. 7 is an elevation of apart of an airplane equipped with a different form of mount which is also constructed according to my invention;

Fig. 8 is a plan view of part ofthe fuselage shown in Fig. 7 and and 18, end with diagonal'bracing elements such as the struts 21, 22 and 23. The airplane fuselage is also provided with a floor 24 The port of the airplane which is disclosed b these drewings is thet odjeccnt to the o servers cockpit. There its-provided for the use of the observer e machine gun 25 (Figs. 1 end 3) which gun mey be of any preferred ty e. I provide menus to support the weight 01: the muchine door 2t us by the bolts 26 end 27 is e bell soclret 2d in which is mounted u bell formed on the lower end-of n hollow rod or tube 29. Thus, the tube 29 is securely tustened tor substentiolly universol movement shoot the hell out its lower end. As will he described inter, the muchine gun 25 is mounted on the upper end ot the tube 29 end is thus supported though cupuble oi ensy movement throughout e consideroble rouge. It desired, the bull socket 2d mey be mounted in o spider uttuched to the longrons insteed of requiring the continuation of the door lunch to this polnt.

hteens ore provided for guiding the upper end of the tube 29 end cones uently the movement of the muchine gun. ecurely iestened to the longerons 11 end 13 us ut ill end 32, is on urcuute guide rod 30. 'lhe rod Ed is provided with n plurolity of holes 33 in the under side thereof for purposes loter to be described, the holes being indiceted by dotted lines in Fig. 2. ll, sleeve ddis pluced over the upper end of the tube 29 end mey be securely testened thereto us by bolts, if desired. Welded to the sleeve 3d end extending substontiolly perpendiculnrly therefrom ore peir oi purullel pletes 35 end 3% of substentielly trinnguler shepe (see Figs. 2 end t). Supported for tree rotution between the plutes 35 end 36 ore three roller beerings 37, 3d end 39. The beorings 87 end 38 ore odepted to contnct with the iorwurd side of the guide rod 30 while the other beoring 39 is udepted to contuct with the reor side thereof. The roller heerings moybe held in position by bolts such no the bolts ti, t2 end 4L3. Thus, it is possible for the sleeve 34 to move in or course odjncent to end eubetentiully purullel to the guide rod dd end therefore the course of the upper oil the tube oil the mochine gun 25 is limited to the desired puth movement. r y

El provide menus tor leaching the pun mount of; soy desired position. its etuted the urcuom guide so termed on the underside thereof plurnlity ot holes lPivotolly mounted gun. Secured to the insurer on the sleeve 34 as at 44, is a bell crank lever having a hand grip 46. The opposite end of the bell crank lever 44 from the grip 46 is pivotal] attached as at 47 to a plunger 48 mounte for substantially vertical sliding movement through a bearing 49 secured to the plate 36. The plate 36 itself is rovided with an aligned ole through w ich the plunger 48 may project upward. Attached to the bell crank lever 44 is a, spring 51 which serves to urge the plunger 4.8 upward to enter the selected one of the holes 33. Thus, when the grip 46 is clasped, the plunger 48 is withdrewn from the hole 33 in which it was previously inserted. 'lhereupon the mount muy be moved by movement of the tube 29 shoot the bell hearing at 28 elong the ercuate guide 30 until at proper position is attained, when, upon release of the grip 46 the plunger 48 will enter o new selected hole 33 and thus ogoin lock the mount. Only one hand is necessery to compress the grip and move the tube 29 while the other may be rctoined upon the mochine gun.

A speciel type of fitting for the adopter of the machine gun is provided. Secured to the upper end of the sleeve 34, as by welding, are u pair of 'l'-shaped bruces 52 and 53, each formed of u pair of strips of metal welded perpendicularly to such other. Thus, the brece 52 is formed of the strips 54 end 55 end the bruce 53 is formed of the strips 56 and 57 Both of these breces ere bent in the form of on are so that a substantially circular opening 58 is formed between them. Secured to the upper end of the two braces 52 and 53 is o section of tube 59 similar to the sleeve 34. 'lhe edspter 60 for the muchine gun 25 (as shown in Fig. l) is so constructed that the gun mey rotete shout two perpendicular axes even while the mount is tired end so that the gun may be aimed us desired. The lower art of the udupter is formed with o pair of plus '11 end 72 which spring sport to grip the edge ut the lower end of the tube 59 but the operotor mey reach in the hole 58 and compress the jnvvs to release the udupter when desired.

it is thought thnt the operation oi the device illustrating my invention will be appurent irom the above description. The observer mey be seated Within the cochpit of nirplune ottending to other duties such us photogrophy or redlo: The muchine gun muy, if desired, be muintuined positioned on the mount. the the other hand, may be preferred to curry the gun oll' o the mental; within the :lueelnge. lit so, vvh ieceesity unless the gun muy be ouichly re end the ions oil the udupter inserted n the tube 5d. The observer muy then g 1 the hood grip dd odd move the mount to s; most edvuntugeous position. Thus, it desired to tire over sidr it: most at position with the ,t udjncc side of the airplane. If it is desired to fire overhead, the most advantageous position is in the center of the guide 30. For intermediate fire, intermediate positions on the guide may be desirable. The force of the wind stream from the propeller aids in moving the gun upward along the track to its elevated position for upward firing and the weight of the gun aids in moving it downward against the wind stream to the ositions at the side.

It is thus clear that the shape and arrangement of the guide 30 is such that' the mount for the machine gun is in a sense automatically elevated whenever it is desired to fire overhead and similarly depressed whenever it is desired to fire over the sides of the fuselage. Thus, it is possible for the gunner easily to put himself in position above the gun when he is firin downward and easily to put himselfin posltion below the gun when he is firing upward. This change of position of the mount insures thatthe gunner shall at all times receive the maximum protection possible from the fire of the enemy, Moreover,

the shape of the guide issuch (as may beclearly seen in Fig. 2) that when .the gunner desires to fire partially forward hemay place his body within the c'urvature of -the guide and thus position himself back of the gun mount in the most convenient position for firing forward. i

It is to be especially noted that the mount for the gun takes very little space in the cookpit, the support 29 extending fortvard, out of the way of any other apparatus 'that may be required. The logical place fonthe camera to be used in photographic missions i's'in the floor of the fuselage just back or the post 29. Thus, the camera may be positioned in the most convenient place without interference with the gun mount and without the gun mount interfering with the operation of the placed in a convenient position. Moreover,

the shape of the guide and the position of the support and of the gun are such that they do not interfere with the ingress or egress of the observer to and from the cockpit.

The mounting upon the roller bearings 37,

38 and 39 and in the ball bearing socket 28 is such that substantially free movement is insured and the tendency of the mount to bind or jam is substantially eliminated. On the other hand the lock plunger 48 insures that the mount shall be securely fixed when it is desired to use the gun in anydesired position,

- without danger of the mount moving until the lock is released. As soon as the gunner desires, however, he may by operation of the handle 46 immediately release the lock mechanism in order to readjust the position of the mount.

In the modification of my invention shown inFigs. 7, 8 and 9 like parts are desi nated by the same numerals as are used in igs. 1

to 6, inclusive. The ip 46' is similar to the grip 46, although a shghtchange in shape has been made therein. The grip 46 is mounted I is'connected to the plunger 48* which is urged int'o locking position by the spring 51. The

sleeve 34 is formed in two parts and comprises an upper part 34 and a lower part 34".

The upper part of the sleeve 34 is formed as one half of a cylinder and the lower part of the sleeve 34 is adapted to fit within said semicircle extension 34 of the sleeve as may be seen by reference to Fig. 9. This construction insures alignment and rigidity. The lower part is secured to the tube 29 in any on a bracket 63 formed on the sleeve 34 and suitable manner as, for instance, by rivets 61.

the cockpit, and effect of the air stream fl0wing over the fuselage. A latch 64 serves normally to maintain the upper part of the sleeve 34 in contact with the lower part 34 as is shown in Fig. 9 and a spring 65 serves normally to hold the latch in locking position. A button 66 is provided by which the spring 65 may be contracted and the latch released.

The operation of this form of my invention is similar to that described in connection with the form shown in Figs. 1 to 6, inclusive. However, when the machine gun is not needed the latch 64 may be unlocked and the machine gun, the adapter and the upper part 34 of the sleeve may be folded back so thatthe gun presents a minimum amount of interference to the observer, and wind resistance.

Thereafter, as may be clearly seen from Fig. camera. Radio equipment may similarly be 8, it is comparatively easy for the gunner to quickly draw the gun back into its normal position by pulling back directly on the gun andles until the parts 34 and 34 of the sleeve are aligned as shown in Fig. 9. Thereupon, the latch 64 snaps into position to lock the parts of the sleeve together and the gun is ready for firing.

It is to be understood that the above described embodiment of the invention is for the purpose of illustration only and various changes may be made therein without departing from the spirit and scope of the invention. V

. I claim as my invention:

1. In amount for a machine gun for an airplane, a support for said machine gun, means for guiding said support, and means for attaching the machine gun to the said support comprising an adapter for said machine gun equipped with resiliently spreading jaws, a tubular element spaced from said support and into which the said jaws are dmosaics adapted to be inserted, and braces securing said tubular member to the said support. 2. In a mount for a machine gun for an airplane, a support for said machine gun 5 comprising alower sleeve, an upper sleeve, a hinge by which the upper sleeve is mounted upon the lower sleeve, and means carried by the upper sleeve for directly supporting the machine gun. 3. In combination, an airplane includin a fuselage, a machine gun, a guide secure to said airplane for movably supporting said machine gun, and means for mounting said machine gun on said guide including a hinge, 15 said fuselage being formed 'vvitha pocket into which said machine gun may be retracted when not in use. v

4. In an airplane, in combination, a fuselage, a cockpit in said fuselage, and a mam} chine gun mount for said cockpit comprising a supportpivoted to the bottom oi said fuse lage rearvvardly of said cockpit, said support extending upwardly above the edge of said cockpit, a guide attached to said fuselage ad- 'jacent the sides of said cockpit and slanting upwardly and rearwardly to a point above 7 the rearward edge of said cockpit, rollers carricd by said support for engaging said guide, a lockin device carried lo said support and 30 engages le with said gui e for holding said support in adjustably' fiuedrelation with respect to said guide, a sleeve hinged to said support above said rollers, and means for locking said sleeve with respect to said support, said sleeve being adapted to releasably hold said machine gun.

5. In an airplane, in combination, a fuselage, a cockpit in said fuselage, and a machine gun mount for said cockpit comprising a support pivoted to the bottom of said fuselage rearwardly of said cockpit, said su port extending upwardly above the edge 0 said cockpit, a guide'attached to said fuselage adjacent the sides of said cockpit and slanting upwardly and rearwardly to a point above the rearward edge of said cockpit, rollers carried by said support for engaging said guide,

a lockin device carried by said support and engageahle with said guide for holding said support in adjustably fixed relation with re spect to said guide, and means associated with the upper end of said support for releasably holding said machine gun.

In testimony whereof ll hereunto an my signature.

CLlBlll l Gr. TRIMBAGH;

Eli 

